To learn to apply the concept of current density and microscopic Ohm's law. A "gauge 8" jumper cable has a diameter d of 0.326 cm. The cable carries a current I of 30.0 A. The electric field E in the cable is 0.062 V/m. Below is a list of some common metals with their:

1) what is the power in horsepower of a 100 watt light bulb? what is the power in kilowatts of a 200 horsepower engine? 2) if a cars engine is providing 3000 n of force to keep the car moving at 5 m/s, what is the engine’s effective power? 3) how many gallons of water will be pumped from a well 30 feet deep by a 1/2 hp engine in 1 minute? (1 gallon weighs 8.34 pounds)